We've all been there. Those days when you've just had enough already. The slightest provocation and you're ready to blow. Maybe you elbow someone a little to hard when they crowd your subway-space. Maybe you pop off on the waitress for messing up your order. Or, if you're like one disgruntled Chinese man, maybe you catapult yourself over the glass-walled ATM vestibule and stab the guy who skipped infront of you in line.

What's more incredible than the absolute rage that must have been pumping through his aggressor's veins is the calm manner in which the cut line-cutter carried on with his transaction. Clearly visible in the final few seconds of the surveillance video is a spreading stain of blood that was not there when the man first arrived. [YouKu]